Fig 1.
Whiskers and corresponding barrel columns and experimental system.
(a) Whiskers and corresponding barrel columns: A schematic representation of the rat’s whisker system and the corresponding barrel columns in the primary somatosensory cortex (S1). The C2 whisker (yellow) is highlighted to indicate its role in locating the C2 barrel column. (b) Whisker stimulation system: The experimental setup for mechanical stimulation of the C2 whisker. The system includes an L-shaped tube, step motor, Arduino UNO R3 controller, A4988 motor driver, Master 8 pulse generator and Cerbus recording device.
Fig 2.
Comparison of EEG signals under different anesthetic protocols.
Alpha-chloralose combined with 0.25% Isoflurane anesthesia is represented in black; Alpha-chloralose combined with 0.5% Isoflurane anesthesia is represented in red; 1.5% Isoflurane is represented in green; and Ketamine-Xylazine anesthesia is represented in blue.
Fig 3.
Precise localization of the C2 barrel column highlighted by red dashed circle in the somatosensory cortex.
Fig 4.
Comparison of barrel cortex LFP signals and corresponding power spectral density (PSD) across different anesthetic protocols.
(a) Barrel cortex LFP signals recorded during whisker stimulation under three anesthetic conditions: alpha-chloralose + 0.5% Isoflurane (red), 1.5% Isoflurane (green), and Ketamine-Xylazine (blue). The time axis represents the duration of whisker stimulation in milliseconds, and the voltage axis represents the LFP signal amplitude in microvolts (µV). The peak LFP amplitude is highest with alpha-chloralose + 0.5% Isoflurane, followed by 1.5% Isoflurane and Ketamine-Xylazine. (b) Power spectral density (PSD) analysis of LFP signals across different anesthetic protocols. The alpha (8–13 Hz) and beta (13–30 Hz) frequency bands are highlighted with shaded regions (pink for alpha, blue for beta). The PSD comparison shows that alpha-chloralose + 0.5% Isoflurane significantly amplifies power in the alpha and beta frequency ranges, while 1.5% Isoflurane and Ketamine-Xylazine show reduced power in these bands.
Fig 5.
Longitudinal comparison of barrel cortex LFP signal amplitudes and latencies under different anesthesia protocols.
(a) Mean and SEM of LFP signal amplitudes across 7 hours: This graph displays the mean and standard error of the mean (SEM) of the barrel cortex LFP signal amplitudes recorded under whisker stimulation for three anesthesia protocols: Alpha-chloralose + 0.5% Isoflurane (red), 1.5% Isoflurane (blue), and Ketamine-Xylazine (green). Alpha-chloralose consistently demonstrates the highest amplitude (~800 µV), significantly surpassing Isoflurane (~400 µV) and Ketamine-Xylazine (~200 µV) at all time points (*p < 0.05). *Represents the significance. (b) Mean and SEM of LFP signal peak latencies across 7 hours: This graph shows the mean and SEM of peak latencies of the LFP signals under whisker stimulation across three anesthesia protocols. Alpha-chloralose + 0.5% Isoflurane (red) demonstrates the shortest latency (~17 ms), compared to 1.5% Isoflurane (~20 ms) and Ketamine-Xylazine (~22 ms). Independent t-tests confirm statistically significant latency differences (*p < 0.05), particularly between Alpha-chloralose + 0.5% Isoflurane and 1.5% Isoflurane protocols. *Represents the significance.
Fig 6.
Comparative analysis of heart rate and body temperature changes over time under different anesthetic protocols.
(a) Mean and SEM of heart rate changes over 7 hours for animals anesthetized with alpha-chloralose + 0.5% Isoflurane, 1.5% Isoflurane, and Ketamine-Xylazine. Statistical significance (*p < 0.05) was observed between alpha-chloralose and Isoflurane groups. *Represents the significance. (b) Mean and SEM of body temperature changes over 7 hours for animals anesthetized with alpha-chloralose + 0.5% Isoflurane, 1.5% Isoflurane, and Ketamine-Xylazine. Statistical significance (*p < 0.05) was noted between alpha-chloralose and Isoflurane groups. *Represents the significance.